Electric connector.



JC. STBARNS.

ELECTRIC CONNECTOR.

APPLIOATION FILED DBG. z2, 191s.

Patented May 1 2, 1914.

'I UNITED sTATEs PATENT oEEIcE.

.uson c. smms, or woncnsrnn., MASSACHUSETTS.

ELECTRIC' CONNECTOR.

` Speoiiication of Letters Patent.

Application inea December a2, l191s. sei-iai No..sos,i42.

Be -it known that I, JASON C. STEARNs, a citizen of the United States,residing at Worcester, in the county of Worcester and State ofMassachusetts, have invented a new and useful Electric Connector, ofwhich the Afollowing is a specification.

This invention relates to a plug or connector for electrical purposesand the principal objects thereof are to provide anab` solutely certaindevice for connecting a circuit when the plug is pressed in, involvingsurfaces which are caused to rub along each other instead of simplycoming into contact in a normal direction; also to .pro-i vide animproved construction of the members for producing this contact;'tofprov'ide'i an arrangement whereby the plug vmember can be turned totwo positionsg'on the rightl and left, in one of which the circuit ismade in theabove mentioned manner, and in the otherjof which, althoughthe plug is firmly Vheld in the socket yet the terminals areI out ofcontact; to provide an improved slot arrangement for securing thisresult; and to provide simplel means whereby the plug cani not be pushedin or pulled out accidentally.

The invention also involves further details of construction which willappear hereinafter.

Reference is to be had tothe accompanyin drawings in whichigure 1 is aside elevation of a preferred embodiment of the invention` showing itapplied to a tail lamp socket and connector plug; Fig. 2 is alongitudinal central sectional view of the same withthe parts in thesame position in which the contact is'made; Fig. 3 is a similar viewwith the parts in the 0E position; Fig. 4 is a sectional view similar toFig. 2 showing a modification used for a wooden dash connector; Fig. 5lis a perspective view of the slit bushing; and Fig. 6 is a side view,partly in section, of certain details.

Referring first to Figs. 1, 2 and 3 it will be seen that the connectingdevice comprises a socket member 10 and a plug member 11. The socket isprovided with a spring-pressed metallic plunger 1.2 therein, in thiscase havi an insulating end 13 formed of hard ru ber-or the like.Surrounding this plunger is a hollow metallic guide 1li which holds theplunger in proper position and prevents its disengagement from thesocket and also has at its outer end a slanting,

socket.

rounded, or conical surface 15.k The guide is shown as ofmet'aLpreferably brass. The guide 1s electrically connected with aAmetallic plunger 9 at the other end of the .throughthe perforated'bottom of this bushintola body of a metallic insert 19 lo- ,"cated' inabushing .19 in the hard rubber body of the lug and connected with thecir- '.cuit in any esired way. The sheet metal of the bushing 16 beingresilient, its three sections press out from the walls of the centralpassage' through the plug and form a. yielding connection. AOn the plug,as usual, are a pair of pins 18 and the socket is provided with slotswhich can be of the general T- shape form but in this case each has itstransverse end 20 inclined at an angle to the longitudinal part 21 ofthe slot. These parts 20 and 21- are for receiving the pins 18.

The length of the slitted bushing is such that When the .plug is inposition with the pins in the extreme portions of the slots 21, the endof the bushing, which is of the same diameter as the end of the guide,comes into contact with the latter. By the turning of the plug to getthe pins into their extreme positions, the guide 14 enters the springbushing and forms a positive self cleaning contact. The fact that thebushing is slit permits a slight yielding in order that this contact maybe more intimate.

When the plug is turned to such position that the pins are in the nearend of the slot 21, as shown in Fig. 3, the insulating end of theplunger isstill engaged in the end of the opening in the plug but itcontacts only with the screw head and there is no electrical contact.Thus, when the current is shut off, the parts are in such position thatby giving them practically only a quarter turn the current can be turnedon.

parts of the". plug member "which 'en'-I As ordinarily applied toautomobiles inv I have s own two of these tongues oppof sitely placed.They are used in connection with any kind of pin 32 and slot 33. .'Ihusthe lampis held in central position and cannot move materially in thesocket. I The tongue 31'also forms a perfect rubbing contact with thelamp base which is important on a wire construction asfshown In the formshown in Fig. 4 the conditions are similar to those shown in Figs. 1,v 2and 3 except that the plunger 26 is metallic clear to the end andconsequently is capable of forming a contact with the screw 27 andcompleting the circuit immediately after the plug is inserted and before.it is turned into its locked osition. In this case there is no need o aT-shaped slot because it is impossible to hold the plug in such positionin the socket that there will be no electrical connection. However, incase of lodgment of dust or other insulatin particles on the screw heador the end o the plunger the turning of the plug around into lockedposition will insure a perfect electrical contact between the end of theguide 28 andthe ,end of the slitted bushing 29. In this case one of theterminals 3,4 is connected with the casing 35 so as to ground it, themetallic casing being mounted on an insulating dash.

It will be seen therefore that the principle involved in the guide andslitted bushing permits of a certain electrical connection whenever thatis desired even in case -of old, worn or even dirty contacts and .thatthe princi le can be carried out in connection with e new form of slotandthe locking Ymeans herein shown with certain advantages which havebeen set forth. f

Although I have illust-rated and described only a few forms of theinvention, I am aware of the fact that it can be carried out Yin manyother. forms and applied to many kinds of electrical connectors andattachments either in the one wire or two wire systems without departingfrom the scope of this invention as set forth in the claims. ThereforeIdo not wish to be limited in these respects but What I do claim is 1. Aconnector or coupling of the class described comprising a socket member,a

' noname described comprising a socket member, a central longitudinalspring-pressed plunger therein, a metallic guide surrounding the plungerand having an inclined end surface, and a plug member having a centralrecess in alinement with said plunger and guide and provided with ayieldinginetallic bush- 1ng 1 n said recess and having its edge inposition vto engage the inclined end surface of said guide when insertedin the socket member.

3. The combination in an electrical connecting device, of a socketmember provided with a hollow guide, a spring-'pressed lplunwith acentral axial hollow guide, a springpressedplunger projecting from theend of said guide, the end of said guide being conical and the plungerhaving a metallic part and a non-conducting end, of a plug meinberhaving a central longitudinal recess extending in from the end, saidrecess being provided with a metallic longitudinally slit lining, meansfor holding said lining in position, and means whereby the plug can beheld in the socket member with the plunger pressed against the bottom ofsaid lining and the edge of the lining in Contact with the conical edgeof said guide.

5. The combination in an electrical connecting device, of a socketmember provided with a hollow guide, a spring-pressed plunv gerprojecting from the end of said guide, the end of said guide beingconical and the plunger having a metallic part and a nonconducting end,of a plug member having a longitudinal recess extendin` in from the end,said'recess being provided with a resilient metallic slit lining, meansfor holding said lining in position, a pin extending out laterally fromthe plug, and a slot in the a longitudinal portion and a transverseportion arranged at an inclination whereby when the pin is the mostextreme part of said transverse portion of the slot, the lining willbein contact with said guide and whereby when the pin is in the lowestpart of said slot the lining and guide will be out of contact.

inal recess ywall of said socket member, saidfslot having" 6. Aconnector Yor coupling of the class de- I tallic guide surrounding theplunger and member whereby when the nut is adjusted to having aninclined end surface, and a plug a certain position it will prevent theplug member having a recess in alinement with moving in the socketmember.

said plunger and guide and provided with a l In testimony whereof I havehereunto set 15 metallic bushing in said recess adapted to my hand, inthe presence of two subscribing be dconnected atdits bottoni with theeircutwitnesses.

an having its e e in osition to en age t e end surface of salinid gliidewhen insrted in JASON C STEARNS' the socket member, said plug having ascrew Witnesses:

thread thereon and a nut on the screw thread Y ALBERT E. FAY,

adapted to engage the edge of said socket l C. FoRREsT WESSON.

